M.B.
My daughter did the same thing at that age. My pediatrician said that as long as they are sleeping all night, not to worry. Some kids don't like to nap. Needless to say I was a little frustrated because I have a three year old who was begging for attention. We never got one-on-one time. I'd still put my daughter down, she'd cry, but I got some time with my son. As she got older she started playing in her crib, and now she eventually falls asleep for her morning nap. I don't even remember when the transition came, but it did. Now she naps in the morning and with her brother in the afternoon. They share a room, so that's great.
Give it time and be consistent. Maybe set a time limit on how long you let the baby cry it out in the crib (i.e. 45 minutes), just to get a break. Schedules will eventually happen, but only if mom stays on schedule.