Urg

Ben is talking more and more. My one frustration for the past month though has been that he won't say "mama, mommy, mom". NOTHING close to it. He'll say touchdown, but won't say mommy. He'll say Jesus, dada, more, please, thank you, Lucy, Ally, Grandpa, Grandma, Hi, Hello, bye bye, there, cow, dog, bird and lots of other words, but WON'T SAY MOMMY. What's with this? I've tried bribing him with m&ms, didn't work. I've tried being really sweet with him, didn't work. I've tried getting him to say it, so I'll take him out of bed, he won't say it. I really think he thinks it's funny and is just holding back on me because he knows he can.