Paul:
A while back, had this scenario:
Service call, partial power out in a home.
Found one 20 amp branch cb triped
HO said "I tried to reset it a few times, but it keeps tripping"
Went thru the affected areas of the house looking for the obvious.....
Checked a bedroom wall, and pulled the bed away from the wall....
Found a quarter (25 cent coin) had dropped from the bed, and bridged the hot/neutral pins on a lamp that was plugged into the receptacle and partially hanging out.
Turns out the boy was counting coins, dropped one, and that's what caused the problem.
Luckily, the arcing didn't set the bed covers afire....he said he tried to reset it numerous times!!
Happy holidays
John