I've read some threads that say toddlers 2-4 years old are not allowed in D1 and others that say they are with approved seating? We are looking at a RT slc-lhr connecting through seattle (to virgin) for next year with what will be a 2.5 year old. It will be paid D1 (toddler with her own seat) but I can't seem to find a definitive answer on if toddlers are allowed at all in D1 'due to the equipment'. I've googled it a lot and again gotten conflicting information. Anyone want to point me to the truth or have any personal experience with this?