Hi Heather!
Welcome to the Disney Parks Moms Panel. How fun for you and your hubby to take on a
runDisney event together!
For yourself, if you register for the
Walt Disney World 5K and then would later like to also add the
Walt Disney World Half Marathon you would just register for the second race, pending it is still available. Since these two race distances are not linked in anyway for a challenge you would not need to change your initial registration. Walt Disney World Marathon Weekend for 2018 is going to be a popular race because it's celebrating multiple anniversaries. In the event it sells out, I'd recommend checking out the charity programs or travel providers to see if they have any bibs left. You can find more information on the
Registration tab.
For your husband, runDisney does allow
transfers if you are upgrading distances, but this is not applicable for the 5K distance. So if your husband registered for the Walt Disney World 10K and then wishes he had done the
Dopey Challenge, and it was still available, he would register for the Dopey Challenge then submit the transfer paperwork to runDisney and they will refund you the initial registration, less a $45 processing fee. Unfortunately this is not an option for the 5K distance or any of the runDisney Kids Races.
I hope this was clear, but if you have any other questions please come back!
-Lindsey ºOº