It's completely normal for bf babies to gain much less the second six months. My DS only gained 8ozs from 6 months-year. He was meeting milestones, happy and healthy. I wasn't concerned. What does your mama gut tell you? I would look at HER and not the scale, what does that tell you?
Fwiw, my DS was 17lbs at 1 year (9lbs at birth), about 26lbs at age 2, and 30lbs at age 3. He's just lean and doesn't put on weight fast. But he's breastfed and eats a ton, lol.
Single Mommy to my 3 year old DS born all natural
. We are a Cosleeping
, Babywearing Non-Vaxing