DD2 is 5mo and about 1.5 hours after she wakes (can be between 7.30 and 9ish, any earlier and she usually goes straight back off) up she has a nap which ranges from 1-2.5 hours. This is only if we are at home mind you. If I dare to go out she doesn't sleep for very long (only if we are moving) and fights sleep for the rest of the day.
This is a very welcome break for me, as DD invariably refuses to go down in the evening. But I wonder if this long nap is having an effect.
If she does have this morning nap she will usually have one or two short naps in the afternoon. Could the long nap be keeping her awake in the evening? I'm loath to wake her really, and if I do and she still doesn't go down in the evening then I will have had very little break between 7.30 and 11.30, with one or two night wakings thrown in for good measure.