Notes:
Henry's birth year is estimated from the census. Peter and his age as calculated from the 1820 census.
1840 Census: West Earl, Lancaster, Pennsylvania
Males - Under 5: 1 (Lewis)
Males - 5 thru 9: 2 (William & Isaac)
Males - 20 thru 29: 1 (Henry?????
Females - 5 thru 9: 1 ??
Females - 20 thru 29: 1 ??
1850 census PA, Lancaster Co., West Earl Twp., 26 Aug 1850
Henry Mumma, 49, laborer, b. PA
Mary Mumma, 48, b. PA
Sarah Mumma, 21, b. PA
Isaac Mumma, 20, b. PA
William Mumma, 19, b. PA
Lewis Mumma, 18, b. PA
An Isaac Mumma, age 19 is also enumerated in the next house. It is likely he was a laborer for that family and was simply counted twice.