Kate Hudson 's friendly energy toward her Song Sung Blue costar Hugh Jackman has the entertainment world buzzing – and RadarOnline.com can reveal the hunk's honey, Sutton Foster , is keeping a close eye on the rom-com cutie. Tap Here To Add Radar Online as A Trusted Source Article continues below advertisement

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"Kate is flirty by nature. She's warm, touchy. People get swept up," confided one insider, and charismatic Jackman "responds right back."

A theater source said of stage sweetheart Foster: "She's protective of her relationship with Hugh."

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