A late discovery supplementation may be allowed if the party shows good cause and a lack of unfair surprise. The Fifth Court reversed a trial court ruling about an expert supplementation when, inter alia: “The record shows (1) Mr. Longeway’s report was based almost entirely on his inspection of the job site’s deactivated electrical lines and (2) the lines’ deactivation could be performed only by the electric delivery company and was not completed until November 30, 2018. Appellants received Mr. Longeway’s report on January 11, 2019, and filed their motion for reconsideration and new trial, with that report attached, several days later. Weekley’s response to the attempted late designation focused only on [another expert’s] report and did not specifically address good cause or unfair surprise or prejudice as to Mr. Longeway.” Paniagua v. Weekley Homes, No. 05-19-00439-CV (Jan. 13, 2021).