W.F.
Hi P....
One technique I'm familiar with is using the baby swing to help. If baby wakes, crying and you've tried all the "normal" things (feeding, changing, etc), try putting her in the baby swing and vigorously rocking it back and forth (kinda shaking it) for a minute or 2... that motion usually comforts a baby, and then put it on HIGH for the swing. they actually sleep WELL in the swing. I KNOW this works well in younger babies... not certain about an 8 month old, but it's worth a try. I'm an instructor of the Happiest Baby on the Block baby calming techniques, and this is one of Dr. Karp's recommendations that I've SEEN work! Good luck!
W.