"There is a boy and a girl" or "There are a boy and a girl".
Since "boy and girl" form a coordination of two NPs linked by "and", it would normally have a plural verb. However, in informal style, especially in present tense declaratives with reduced is, many speakers treat there as always singular; they would say There's a boy and girl.
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Since "boy and girl" form a coordination of two NPs linked by "and", it would normally have a plural verb.
However, in informal style, especially in present tense declaratives with reduced is, many speakers treat there as always singular; they would say There's a boy and girl.