He is very cute! I hope you have a nice visit!
I think his size will be fine. In my house, we have a variety: 2.5 pounder, 5 pounder, 8 pounder and 80 pounder. Everyone plays and everyone is fine

I do have to tell the big guy to settle down occasionally as he forgets he is not a small dog too. And sometimes I have to tell the little guy to leave the big guy alone as he likes to kiss on him incessantly

, other than that, we do just fine.