On one episode she plays a def mute child that witnessed a murder ...

S3.E23
Deaf Mute

Episode aired Mar 10, 1958
https://www.imdb.com/title/tt0853642/mediaviewer/rm2827067905/?ref_=tt_ov_i

A husband (Fred) and wife (Edith) attempt to rob a small rural grocery store at gunpoint. The robbery results in critical injury to the grocer and the abduction of the only witness - the grocer's 10-year-old daughter, Susie. The terrified girl can neither hear nor speak and elicits sympathy from the compassionate Edith, who eventually convinces Fred to release her in a remote area. Dan Mathews is disgusted that anyone would abduct such a helpless victim and orders an intensive search for the child. When Officer Harper finds her unharmed, Dan discovers that he is able to take advantage of Susie's lip-reading and observation skills to obtain critical information concerning Fred and Edith and their possible whereabouts. When Officer Harper subsequently spots Fred and Edith's station wagon, he chases them back in the direction of Dan and Officer Dennis. An armed confrontation becomes inevitable.

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7.0
TV Series

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1966–1970

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TV Series

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1967

William Frawley, Don Grady, Stanley Livingston, and Fred MacMurray in My Three Sons (1960)
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7.1
TV Series

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Gidget (1965)
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6.9
TV Series

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1965–1966

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7.2

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1961

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7.6
TV Series

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1960

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7.7
TV Series

Susie Haskell