Once he went on a cycling trip with the Bloom sisters and broke his leg on the trip, but later married both of the sisters. He was still married to one of them in 2367. Picard described Louis as a "desperately poor swimmer".
In 2367, Louis was the supervisor of the Atlantis project. He wanted Picard to take lead of the project and even arranged a meeting with government officials for him, but ultimately Picard cancelled the meeting and declined the offer. (TNG: "Family")