unwrapping b'day pressies,- when? etiquette?

[linspins]

My dd is having her 4th birthday party tomorrow, at home with 9 guests. What's the etiquette for unwrapping presents? We've been to some parties in halls recently where the presents were just piled on a table upon arrival and never seen to be opened. But another party, in a house we went to, the child unwrapped her pressies immediately she was given them. What do you think is best?

Unwrap in the privacy of your home. Always!

Children that age are likely to be both a) overwhelmed and b) excessively frank about what they think of the pressies.

During a small party at home with just a few guests, it might be perfectly OK to open the presents there and then. I would have thought that when the party is at another venue and/or has more guests, the reason for not opening presents immediately would be practicality as much as anything i.e. not wanting to have a mountain of wrapping paper to deal with/keeping presents attached to the label that tells you who gave it (for thank you cards)/not halting proceedings for an interminable period/minimising the opportunity for comparing prices gifts. Much of that doesn't apply to home parties especially with just a few guests.

Unwrap pressies after the party.
That way you avoid any competitive parents seesing/comparing who has spent the most money etc.
As parent you will have time to make a note of who gave your DD what (and arrange for proper thank you letters to be written).
Children at a party are too excited to
a) sit around while the birthday child opens presents
b) for birthday child to really appreciate the gifts
c) a guest will always want to play with the birthday child's favourite present (cue tantrums)
d) they don't understand while the unwrapped gifts are removed as soon as they are unwrapped.
Finally, opening later spreads out the enjoyment for a couple more hours.

If there's time at the end of the party, your dd could unwrap the presents with her guests.

Good advice all, thanks everyone.
Wish me luck today, the weather forecast is rainy and i'd really hoped to be outside with them all!!

Here - you can borrow my tin helmet.
Good luck.