Question about homemade beer, the bubbler?

my husband made a batch of homemade beer. the bubbles coming up are very foamy and its dripping a little up and out of the bubbler thing up top. Is this normal? we made a pumpkin ale. I know its supposed to bubble but am not sure if it should bubble this much or even turn to a foam. Sorry if this sounds stupid. I've never made beer before. My husband hasn't done it in awhile so I've never witnessed the process