The San Francisco Giants shortstop Brandon Crawford, who happens to be the brother to Cole's wife Amy, cheered on Cole during Game 5. The 29-year-old right-hander was also joined by his niece and nephew.
Cole helped the Astros win 6-1 against the Tampa Bay Rays, and set a franchise record by striking out 15 batters.
Crawford, who also attended UCLA alongside his sister and Cole, is known to support his brother-in-law when they're not facing off.
During one game, Cole signed a pair of cleats saying "outta here" and "Adios, pelota" and sent them over to Crawford as part of their friendly rivalry.
Off the field, the families enjoy their time together like many in-laws do, taking their children on group outings.
Last year, Amy Cole and Brandon's wife, Jalynne each posted photos on social media showing the families enjoying an off-day at the Aquarium in downtown Houston.
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