Flight for family of 15 with small children and only 2 seats together.

We booked tickets for 15 family members, including 6 small children ages 2 to 11, for a vacation. When we booked the tickets, we entered the ages of the passengers. We were not able to see the seat assignments until 24 hours before the flight, at which time we realized only 2 of the 15 seats were next to each other. When we called customer service and spoke to a supervisor to try and help us, she said "our job is to get you from point A to point B; our job isn't to keep you together." Their suggestion: negotiate with other passengers as we are boarding to try and get seats together.