Internet Archive Book Images (1830), No restrictions, via Wikimedia Commons
Scan from the original work from Urania für 1820, Public domain, via Wikimedia Commons
Laertes is a character with very few qualms about avenging his family after they have been wronged. He vows revenge on Claudius for the death of Polonius and madness of Ophelia, jumps into Ophelia's grave right after Hamlet, and agrees to a rigged duel with very little deliberation. This positions him as perhaps a more ideal protagonist to a typical revenge play: see "A (sort of) Revenge Tragedy" for more on this.
Seeing as I gave Ophelia a Taylor Swift song, it feels only fair to do the same for Laertes. Above is the one I found most fitting.
Hamlet et Laertes dans la fosse d'Ophélie, Eugène Delacroix (1843), British Museum, Public domain, via Wikimedia Commons
The relationship between Laertes and Ophelia as brother and sister begins with Laertes assuming a Polonius-like position of advisor to his sister, warning her of the dangers of pursuing a relationship with Hamlet before departing for France. As a sister/sister relationship, Laertes' advice to Ophelia seems to stem from the care of potential shared experience rather than the impressively patriarchal advisement of an older brother.
Below is a music video with an original song I found that plays with Laertes and Ophelia's relationship to each other and to Hamlet. Interesting gendered things abound!
Ophelia and Laertes, Benjamin West, CC0, via Wikimedia Commons
Internet Archive Book Images (1866), No restrictions, via Wikimedia Commons
The feud between Laertes and Hamlet over Ophelia place them figuratively as each other's foils. Where Hamlet thinks and delays and pushes off killing Claudius until the last moment, Laertes vows revenge, follows a plan, and succeeds (minus being killed himself by his own poisoned blade).
Below is a silent clip from a version of the final duel between Hamlet and Laertes. An interesting feature of this is the giant rooster overlaying the frame, which brings to mind "East Texas Cockfighting and Hamlet", an article that can be found in full at the bottom of the Hamlet page, if it is of interest.