We bought our 10yo daughter guinea pigs for Christmas. The feed store (a tiny little local store, 3 guinea pigs) sold us their breeding stock, and said one female was expecting babies, and should have them by the end of December. So today is the 25th of January now, and still no babies. She is getting very fat, but we feel no babies in there, like we always feel with our mama cats. I've read that gestation is longer when there are less babies, and mortality rate is higher when there is only one or maybe two babies. Is there any way to tell if this little fat girl is preggo, or if she is just fat? She and the other female, who was with the male when we bought them (hopefully she's pg too), live together in a 4ft square enclosure in the house. They have tunnels to play in, and plenty of room to move around. She shouldn't be just getting fat for no reason, should she? Any input/ideas?