I'd be happy with an E2EE solution that could be deployed on a cheap VPS. Unfortunately, all the photo and video hosting solutions I've come across lack E2EE. Building it out myself is a daunting prospect because it would mean putting together mobile apps for both Android and iOS that supported it as well.
It should be fairly trivial to deploy a number of existing FOSS photo hosting solutions to a server in your house though. Syncthing should make for trivial replication between the local instance and one at a relative's house. It recently gained support for E2EE (ie untrusted servers) so you could even throw it up on a cheap VPS as an extra backup and to allow for more reliable distribution between nodes. There's no bandwidth aggregation to be had here with current tooling though.
It should be fairly trivial to deploy a number of existing FOSS photo hosting solutions to a server in your house though. Syncthing should make for trivial replication between the local instance and one at a relative's house. It recently gained support for E2EE (ie untrusted servers) so you could even throw it up on a cheap VPS as an extra backup and to allow for more reliable distribution between nodes. There's no bandwidth aggregation to be had here with current tooling though.