I know that I read that around 13 mo, babies are still in a 'passive' stage for language. Def look for more signs that LO is learning/understanding language. My LO knows maybe 4 or 5 words to speak them: mom, dad, Ai yai yai, yeah. However, we have named some of her favourite toys and I will say "Can you pass me Christopher?" (her fav stuffy) and she will bring him to me so I can cuddle him. I say 'no' and she shakes her head. We try to do this with yeah or yes, but that of course hasn't caught on yet, haha. She will also feed me a cheerio or hand me the computer mouse when I ask for it; is always pointing and making sounds of interest.
What I've learned is that talking and having conversations with your baby, narrating everything, and reading are the three best things you can do to help your child learn. Good tips in general. But I wouldn't worry too much at this age.