Learn German: Der Hund wurde müde, deshalb streichelte das kleine Kind ihn. - The dog got tired, so the little child petted him.

streichelte is the simple past of the regular (weak) verb streicheln (to pet). To form the simple past for regular verbs, you take the verb stem (streichel-) and add the past tense marker -te. Because the subject is the third-person das kleine Kind, no extra ending is needed.

Why does the verb streichelte come before the subject das kleine Kind?

The clause starts with deshalb (therefore/so), which is an adverb. When an adverb takes up the first position in a clause, the verb must stay in its strict second position. This forces the verb streichelte to come immediately before the subject.

Why use the pronoun ihn at the end instead of es?

In German, pronouns must match the grammatical gender of the noun they replace. Because der Hund is a masculine noun, we must use a masculine pronoun. Since the dog is the direct object receiving the action, we use the accusative form ihn.

Is wurde also a regular verb in the simple past?

No, wurde (got/became) is the simple past of werden. Unlike streichelte, which is a regular verb that adds a -te ending, werden is an irregular strong verb. It changes its internal stem vowel to show the past tense instead of using the regular marker.