It sounds like a great match
In the last year, we added a high energy 2 year old into our house with another high energy 7 year old and a very mellow 10 year old. The 10 year old liked the young one, but at a distance. The 7 year old finally got the playmate she always wanted
! Today, they are 2 peas in a pod
Be prepared for the usual issues while the dogs work our their dominance positions, but if they're a good energy match, that's a big plus.