Should I book a separate seat for my infant?

If you can afford it, yes. A car seat provides a familiar sleeping environment for the child and is safer during turbulence.

What happens if the airline website doesn't let me select seats together?

Call the airline's customer service line immediately after booking. They can often manually force a seat assignment for families with children under 12.

Booking flights for traveling with children

Book your tickets as a single reservation to ensure everyone is linked in the airline's system, which protects your seating arrangements. Always select your seats immediately after booking to avoid being split up, especially for children under 12.

Search for tickets as a single booking. Enter the total number of adults and children in one search query. Booking them together on one reservation code (PNR) ensures the airline knows you are a traveling unit, which is vital if flights are delayed or canceled.
Check the seat map before finalizing. Before you pay, click through to the seat selection page. If the only available seats are rows apart, look for a different flight. Do not assume the gate agent will be able to fix seat gaps once you are at the airport.
Add infant-in-lap status correctly. If you have an infant under 2, you must select 'infant on lap' for the child. This usually involves a small fee (often 10% of the adult fare plus taxes) on international flights, but it is free on most domestic flights.
Verify your confirmation and meal requests. Once booked, call the airline or use the app to ensure your PNR reflects all passengers. If the flight is over 6 hours, request a 'child meal' (CHML) at least 48 hours before departure.

Should I book a separate seat for my infant?: If you can afford it, yes. A car seat provides a familiar sleeping environment for the child and is safer during turbulence.
What happens if the airline website doesn't let me select seats together?: Call the airline's customer service line immediately after booking. They can often manually force a seat assignment for families with children under 12.