The photo of M2 was a random accident, it wasn't until later that I realized we had the same pose from M.G. After that it was something I kept in mind. They all reach a point where the CD play is no longer background wall and instead is something with buttons to push!
M4 found it just a day or two after crawling - faster than the others who crawled around ignoring it for a while. My labels don't show very well - M.G. and M2 were 7 months, M3 was 9 months, and M4 is 8 months. His photo is fuzzy because he was distracted by other kiddos and wouldn't sit still. I just find it funny that they all look back to make sure they really aren't supposed to be touching it!