The fastest way to do this would be to recreate the replica:
1. Unregister the replica from each geodatabase
2. Delete the feature class in the child geodatabase
3. Replicate the data from the parent to the child geodatabase again
But won't step #2 delete the features added to the child by the field walker?
Before you delete the child feature class, may I suggest you make a comparison of the parent to the child. Make a spatial selection of everything in the child that is the same in parent; then switch the selection of the child, and you should have just the field walker additions. Write those to a feature class so you can load them or otherwise get them into the parent.
Hope this helps-
Thanks JS and jborgion.
jborgion you're right, on step #2 it will delete everything that field walkers captured, which is not what we want. The idea is to run this daily check automatically at the background. Probably can build a model based on your suggestion. However, then it's really no need to use database replication.
I thought this (restore the deleted records to Child) could be easily done by Database Replication, as it assigns a GlobalID to each record in the parent, then it shouldn't too hard to compare the two and transfer whatever is missing from the parent to Child.