For safety reasons, no passenger can be responsible for more than one infant. If you are travelling with infants (i.e. children who will be under age 2 for your entire trip), here are the steps to include them in your booking:

Book your flight for all the children, youths and adults in your party. Remember to enter zero (' 0 ') in the 'Infants' field.
Contact us immediately after you’ve booked your flight so that we can update your booking with your infant's information. (Taxes/fees will apply)