Is it Mutar to take family pictures during the nine days? We would like to do them while everyone is around which we won’t be for quite some time…
Yes, this is fine.
That which the Sages forbade is forbidden, and that which they didn’t is permitted.
Although taking family pictures is a relatively pleasant thing, so are many things that are not prohibited in the Nine Days, and it is permitted to do so.
It is worthy practice to follow the spirit of the time and refrain from parties etc. However, where this is a good time for it due to relevant circumstances, it is fine to go ahead.