i want to get apple music for my family but one chikd has a diffrrebt apple id than the rest of us. is that an issue

You actually must have different Apple IDs to share Apple Music as a family.

To share an Apple Music Family plan, you use Family Sharing, which is built on everyone having their own Apple ID.

See >>> Set up Family Sharing - Apple Support

Hello,

With the family plan subscription you can add your family members for Apple Music. Apple ID wont be an issue. Visit this link for information. https://support.apple.com/en-gb/HT205595

-Chris