Date: 201508
Local time of day: 0601-1200
Aircraft: EMB ERJ 170/175 ER/LR
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Cruise
Reporter organization: Air Carrier
Reporter function: Flight Attendant (On Duty)
Human factors: Situational Awareness
Anomaly: Deviation / Discrepancy - Procedural FAR; Deviation / Discrepancy - Procedural Published Material / Policy; Flight Deck / Cabin / Aircraft Event Passenger Misconduct
Detector: Person Flight Attendant
When detected: In-flight
Result: General None Reported / Taken
Contributing factors: Human Factors
Primary problem: Human Factors

Narrative: During the main cabin beverage service the Flight Attendant (FA) B and I noticed a second lap child that we didn't account for during weight and balance. The child was sitting on the woman's lap in seat 10A. After the beverage service we looked over the paperwork and there was only supposed to be one lap child in 16D; which was the only one we had accounted for during weight and balance. The B-FA and I approached the father of the family who was sitting in seat 9C; since the woman in 10A didn't speak English for us to ask her about the child. During the weight and balance and final compliance check before take-off we had not seen the lap child at all in seat 10A. The woman with the lap child was Middle Eastern and had a burkha and a lot of dressing covering the lap child under her burkha; therefore; we decided that the child was hidden during this time and that's why we didn't catch it.Further into our investigation we asked the father in seat 9C how old the child was. He told the B-FA and myself that the child was 3. We asked the father why the child wasn't in their ticketed seat since she isn't a lap child and had her own seat. The father replied that the child was sick so the mother was holding her. Very confused at the situation and where the child came from we proceeded to collect all of their boarding passes to try and figure it out. He handed the B-FA and myself 10 boarding passes total; for him and his group of 10. Each boarding pass had a ticketed seat that included no lap children. This family was scattered throughout the cabin and many of them were not in their correct ticketed seats making it even more challenging to solve. We noticed on the paper work that there was a non-revenue passenger assigned to seat 17D; who was actually sitting in 5F (the seat that belonged to the family of 10). Because the family was scattered all over the aircraft and not sitting in their correct seats we are unsure how the non-rev ended up in 5F and why there was another passenger in 17D.We notified the captain about the issue and we were all very confused how the gate agent boarded 70 people on a 69-seat aircraft. In conclusion we believe the gate agent forgot to scan one of the boarding passes for the family of ten; therefore she assigned a seat to a non-revenue passenger on a full flight. Had the woman not had been wearing a burkha and excessive dressings that covered the child-- the child would have most likely been noticed before take-off.




Synopsis: Air carrier Flight Attendant reported customer service boarded 70 passengers on their 69-seat aircraft and no one caught the error.