This is, according to the artist, the fixed version of post #7991753. From the twitter replies:

I thought it would take me 2 hours to fix it, but it took me 15 instead XD
You can watch the full speedpaint on my YouTube channel ✨ (link in bio)

ignoble said:

This is, according to the artist, the fixed version of post #7991753. From the twitter replies:

You should mark it as the parent then and update other children.