I had the same thing going on as mmaxe01. I had my builders on bath but when I realized I needed to do the hut to grow my village I put 5-6 master builders and 2 or 3 adept builders on the hut with my Chief leading them. As long as I was watching they built. If I minimized the game and then brought it back up, everyone was walking back to the hut from the bath like they knew they were being naughty little villagers and should be working the hut. Thought it was cute at first but as time passed and my hut didn't progress, not so much.
I had it on fast and it took a few hours to get it to about 60% complete. Threw some logs on the fire, moved it to slow, checked the time on the fire (25 hours or something) and turned it off. When I turned it back on tonight the fire had about 10 hours left on slow clock and my building was on about 75% (15 more than when I closed it) My bath had increased by about 15 too so they were working. Once I changed it back to fast and started watching, I got last 25% of the hut in about an hour. (during the time I was away there was an event that paused the play and I can't find the event log so I only have a rough time based on the fire how much work time they actually had)
Age wise, I had a mother carry the child for 123 min, let it loose and she was 7 before the hut was complete.
I don't think this is so much a _bug_, more like something that after you get the major problems fixed, it could be looked at to at least speed up the build time and maybe tweek their concentration span! 9 years is kinda a long time to wait to have kids when your ready to expand!
LOL, it kinda reminded my of the little buggers in the early days of VV2; starving to death over coconuts instead of farming! Only this time, they can't have babies because they are desperate to take a bath!