Revealing mistake: Near the end, right when "little wonders" starts, Lewis takes a moment to look at his future family, Lucille, Frannie, etc. When there's a closeup on Lewis, his memory scanner reveals a reflection of no one in the gym, except for Lewis, even though people are supposed to be standing in front of him.
Revealing mistake: When Lois looks in the driver seat of the bus, there is a mechanical doll there that turns its face towards her and holds up a kitchen knife. The doll has a missing eye, and this is shown in the reflection on the knife. But the crack that is under the hole where the eye is missing is not fully reflected. (00:36:20)Quantom X
Revealing mistake: When Grandpa is being rolled out of the church, everyone is looking at him. As this happens, look closely at the Squeaky Voiced Teen sitting next to Hans Moleman on the right hand side of the church. As he turns his head around you'll see his eyes disappear as he stops turning his head. (00:06:05)Casual Person
Revealing mistake: When the Level 3 Sentry is firing up into the air for no apparent reason, it fires some rockets with a clear defined smoke trail behind them and disappear off screen. Then the shot jump cuts to further away and suddenly the smoke appears again, but the end of the smoke trails are solid and crisp indicating the animators used the smoke animation as if the rockets had just been fired from that spot... in the middle of the sky. (00:01:10)Quantom X