Hi there,
It sounds like you're asking for somebody else...if that's the case, does the person have another, older child?
I ask because my now 5-month old daughter has never really pooped regularly at all, and when I asked her doctor about it recently, she said that it might be that I'm not drinking enough water. With chasing after a toddler and taking care of baby, I forget to drink water!
Sure enough, when I try to have a water bottle with me at all times & drink more, my daughter poops more!
Another thing that I noticed with my daughter not pooping often - her toots stink!! I had feared maybe a food allergy to something I was eating, but my doctor agreed that it might be because waste wasn't passing through, and even fermenting a bit...resulting in one of the stinkiest little baby girls I'd ever encountered! lol But, as I'm drinking more & she's pooping more, she's not as stinky when she toots. Funny how it's all connected, eh? :)
Anyway, that's my 2 cents. :)