Sorry, but your answer was rather discouraging because I myself was the one who made the entry, both on Ancestry.com and Family Search
for William Slack (1799-1837). I am doubting the entry because William and Lucinda, from all the research I've done shows them having only three children. If William (1827-1883) is considered their child also, (a fourth), then that means he and his sibling Sarah were both born in 1827, just two months apart - an impossibility! As for your comment "you can do more research", I guess I can but was looking for outside help as I have been researching on the parents for about one year now!