Reddit mentions of Nektar, 49-Key Midi Controller (SE49),Black white Grey

you just need to get a decent DAW program for making the actual music part, most have an entry level version for about $99 and you can find these bundled with most MIDI controller keyboards as well (having an actual keyboard will make composing and creating MUCH easier and quicker for her - if you already have one just check to see if it has a USB port for connection to the computer and you can use that - it may also or instead have standard midid-din ports (large round ports) - else look on amazon for one, you can find them for as little as $40 or so but these will be lower end ones with mini keys and harder to use - the $70-$100 or so range is the best to start with, you will find many options with 49 keys and this is sufficient to both create music on the computer more easily and also learn some actual piano playing, as far as one want's to go - learning "piano" or keyboard is not required at all though, simply having the device will be a big help because you can easily learn the basics of scales and chords and improvise melody ideas and simply record them in instead of needing to know some music theory upfront to draw them manually into an editor with the mouse, a sometimes slow and frustrating process if you don't know what your doing (consider for example the analogy of typing on a physical computer keyboard vs using a mouse to click in letters on an onscreen virtual keyboard, even if you cant type the physical one will be much faster and easier than a mouse could ever hope to be for the task of writing words)

note however that "midi controller keyboard" is generally just that - a midi controller, it will not produce any sounds on it's own without the computer software or some external hardware synthesizer or sound module device, it is simply a controller without a speaker or any sounds - if you prefer you could opt for a home keyboard instead such as various casio and yamaha options, most over $100 will offer usb-midi functionality and will work as midi controllers, and then you also can use the sounds they have (though this would requiee an audio interface to record them into the computer or at least an audio cable to go into the computer's audio input jack)

also if you happen to have a mac apple's garageband daw would be suitable for getting started with music, it's a bit limited but it has a quality set of sounds to use for sure - however it would be better to learn one of the more standard major DAW programs as they offer far more features - PreSonus Studio One which is bundled with Crypton's Vocaloids (for free basically), is $99 by itself and some midi controllers bundle it as well, there is also however a free version available for download, this might be a suitable place to start and you could simply upgrade to Artist later for that price - the free version only includes the basic set of instrument sounds but many of these are still quite decent and usable for a beginner (check my first original here: https://www.youtube.com/watch?v=cKzF8_2mDgM - entirely studio one, the old version 2 sounds i believe are all included with the free Prime version, available here: https://www.presonus.com/products/Studio-One/get-studio-one and the current free version will include some better/newer stuff in additon) - the limitations of the free version should not hinder an absolute beginner much for a while, and you can just upgrade later - note that with studio one 3rd party VST plugins (except any bundled with a "special" version of it, such as the Piapro Edition included with Crypton vocaloids will run the included Piapro Studio editor plugin but nothing else) are not supported in the Artist entry level version - but this feature can be unlocked for a nominal additional fee, or you could buy the full Professional version but this is far beyond the needs of a learner

i recommend studio one alot it's very easy to learn and a simple and consistent workflow, i would have had a harder time with something else

it's worth considering also however the style of music she wants to make - studio one is more designed for recording bands and things than deep electronic music production (the genre), something like FL Studio or Ableton Live (a lite version is bundled with many midi controllers) is much better suited to those genres of music and they have the same $100 entry level versions, but no free versions (except when the entry one is bundled with a device) - also there is Bitwig Studio, it's entry version is called Bitwig 8-Track, and it operates similarly to ableton live but has many unique and powerful features for working with external hardware - it is limited to 8 midi/audio tracks but you can combine tracks together (known as bouncing/mixdown) to get more out of this - and it does allow 3rd party vst plugins (note that bitwig/ableton/flstudio work quite differently from other standard nonlinear DAW's and there are special led pad grid midi controllers designed for their unique workflows, but these are not required to use them effectively)

sorry this is getting abit long, i will make some template explaining all of this someday so i dont have to keep writing all this stuff again and again 😅

i think for your case i have come up with a recommendation that will be suitable and affordable, without comitting too much since your unsure how deep this music stuff will go for your daughter

my first recommendation remains a Crypton Vocaloid like Miku/Luka/Rin&Len/Meiko/Kaito because they all include everyting you need to get started making original music (except a keyboard), and even buying one of those AND another 3rd party vocaloid from another company such as Internet Co's Gumi English (The included Piapro Studio Editor can support any Vocaloid matching the engine version of the Crypton it comes with - Meiko and Kaito are v3, the rest are v4 - you just have to do a simple website registration process to get an activation code for the Piapro editor to load 3rd party voicebanks in) - would be cheaper than buying for example Yamaha's Vocaloid 5 editor and whatever desired voicebank.

My second recommendation though, I guess would be to get the Gumi English starter pack that OP got (this is more expensive than any Crypton bundle and does not include a DAW) - you have to get the starter pack in this case because you need the Vocaloid Editor - Cryptons include their own Piapro Studio vocal editor that is easier to use than Yamaha's) - and then for a DAW you could get Studio One Prime for free, and also get Bitwig Studio 8-Track bundled with a Nektar midi controller such as the SE49 ($90 https://www.amazon.com/Nektar-SE49-49-Key-Controller-Keyboard/dp/B01MF9EJPG/ref=sr_1_6?keywords=nektar+midi&qid=1574020877&sr=8-6) - i own the fancier LX49 and it is wonderful) so she can use free VST plugins found online (or buy additional ones later) in her songs, and combine and use both DAW's sounds and features in her music, and this would also allow her to learn multiple ways of working, the more standard linear way and the clip launch method of ableton and bitwig

it would be cheaper however to buy Miku v4 english ($139) or Luka v4x ($169, includes multiple english and jp banks), and then buy just the Gumi English voicebank seperately ($78 download from Yamaha's voicebank store "Vocaloid Shop") and use Piapro instead of Yamaha's editor, and add a midi controller ideally - again you can find various cheaper ones but they will be more limiting and compact

I started with Miku v3 English and the included Studio One / Piapro Studio and a 49 key Alesis Q49 midi controller, for Christmas in 2013, ive since spent many thousands on music stuff even though i've not yet completed a 3rd original, but it's wonderfully fun and has enriched my life, your daughter is blessed to have discovered Vocaloid and i hope you can help her express her creativity and have fun actually making songs - even if she just did covers mostly that's still pretty fun, and maybe if she really became good at it one of her songs might be performed at a concert someday! thats whats so special about all of this, all of these virtual singer's songs are all made by their fans, it's really something special and being a tiny part of it musically fills me with pride - and in terms of a value proposition, consider the skills and enrichment music creation or an instrument can give to anyone of any age, all for about the cost of a game console

good luck sorry this got so long, if you have any other questions feel free to ask, i think ive covered everything about getting the stuff to get started 😌🙋🏻‍♀️🥳🔊🔊