<Table> <Tr> <Td> </Td> <Td> This article's lead section does not adequately summarize key points of its contents . Please consider expanding the lead to provide an accessible overview of all important aspects of the article . Please discuss this issue on the article's talk page . (December 2015) </Td> </Tr> </Table> <Tr> <Td> </Td> <Td> This article's lead section does not adequately summarize key points of its contents . Please consider expanding the lead to provide an accessible overview of all important aspects of the article . Please discuss this issue on the article's talk page . (December 2015) </Td> </Tr> <Table> <Tr> <Th_colspan="2"> "Do I Know You?" </Th> </Tr> <Tr> <Td_colspan="2"> How I Met Your Mother episode </Td> </Tr> <Tr> <Th> Episode no . </Th> <Td> Season 4 Episode 1 </Td> </Tr> <Tr> <Th> Directed by </Th> <Td> Pamela Fryman </Td> </Tr> <Tr> <Th> Written by </Th> <Td> Carter Bays, Craig Thomas </Td> </Tr> <Tr> <Th> Production code </Th> <Td> 4ALH01 </Td> </Tr> <Tr> <Th> Original air date </Th> <Td> September 22, 2008 (2008 - 09 - 22) </Td> </Tr> <Tr> <Th_colspan="2"> Guest appearance (s) </Th> </Tr> <Tr> <Td_colspan="2"> <P> Sarah Chalke (Stella) Heidi Herschbach (April) </P> </Td> </Tr> <Tr> <Th_colspan="2"> Episode chronology </Th> </Tr> <Tr> <Td_colspan="2"> <Table> <Tr> <Td> ← Previous "Miracles" </Td> <Td> Next → "The Best Burger in New York" </Td> </Tr> </Table> </Td> </Tr> </Table> <Tr> <Th_colspan="2"> "Do I Know You?" </Th> </Tr>

Who played april in how i met your mother
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