Answer:
Sing me to a baby about to go to sleep.
I am free the first time and the second time, but the third time is going to cost you money. What am I?
Never ahead, ever behind, yet flying swiftly past, for a child, I last forever, for adults, I'm gone too fast.
If you lose me you may cause people around you to lose me too.
Although a human shape I wear Mother I never had; And though no sense nor life I share in finest silks I'm clad. By every miss I'm valued much beloved and highly prized; still my cruel fate is such by boys I am often despised.
Runs over fields and woods all day. Under the bed at night sits not alone, With long tongue hanging out, Resting at your feet until we go for a walk