Marvin Gaye’s children aren’t backing down in their lawsuit against singer Robin Thicke. The late singer’s children presented audio evidence of copyright infringement by Thicke to the judge on Monday.

The Gaye children gave the judge an audio mashup of Thicke’s smash hit “Blurred Lines” and Marvin Gaye’s “Got to Give it Up”, according to BET. the children say that the mashup proves “concrete musical illustrations of the substantial similarities” between the songs.

That wasn’t all though, the Gaye children also pointed out similarities between another Thicke song “Love After War” and their late father's single “After the Dance.” The children also hired a musicologist for the case, who found eight similarities between “Blurred Lines” and “Got to Give it Up.”

Thicke and producer of the track Pharrell Williams first filed suit against the Gaye children last year, citing a declaration of non-infringement Billboard reports.

Thicke and Williams accused the Gaye children of “smelling money” when “Blurred Lines” became a smash hit. They then filed a countersuit against the two last October. The children of the famed singer are also using Thicke and Williams’ interviews about their father as an admission of guilt, citing several interviews in which the two musical talents mention Marvin Gaye as a powerful influence while they were working on the song.

The case will carry out into next year when a jury trial is set to start in February.

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