If it's not in the credits then I have no idea, but sometimes the singers and voice actors post on social media about the movies. If I find out who it is then I'll let you know (maybe she tweeted about it lol)

@XTinkerBellx Thanks. It's kinda sad Mattel doesn't give artists proper credit for their songs. Like I still don't know who sings Sister Love on YouTube. It's obviously not Barbie. It might be the same singer in Big City Big Dreams, but maybe not. Sister Love also sounds like it was sung by a Black woman

Yeah it's a shame they don't credit them. They used to even have the singers be in the music video (like Brie Larson, Katharine McPhee and Kiana Lede) but now we don't even know the singers' names :(

Now that you mention it, I compared Sister Love and Big City Big Dreams and I also think it might be the same singer? I wonder who she is 🤔

I also wanted to know that...but what makes you think it could be someone black?

I actually wanted to know singers for Barbie Extra songs and Sugar Plum Fairy Nutcracker Remix. They're from different singers as well.

@XTinkerBellx Could you send the video link where the singers are seen within the video?

The singer sounds like Kelli Wakili (the spelling might be wrong, pardon me!) who sang Brand New Sound.