One verse

Srimad Bhagavatam 10.11.39-40

10.11.39-40

क्‍वचिद्वादयतो वेणुं क्षेपणै: क्षिपत: क्‍वचित् । क्‍वचित्पादै: किङ्किणीभि: क्‍वचित्कृत्रिमगोवृषै: ॥ ३९ ॥ वृषायमाणौ नर्दन्तौ युयुधाते परस्परम् । अनुकृत्य रुतैर्जन्तूंश्चेरतु: प्राकृतौ यथा ॥ ४० ॥

kvacid vādayato veṇuṁ kṣepaṇaiḥ kṣipataḥ kvacit kvacit pādaiḥ kiṅkiṇībhiḥ kvacit kṛtrima-go-vṛṣaiḥ vṛṣāyamāṇau nardantau yuyudhāte parasparam anukṛtya rutair jantūṁś ceratuḥ prākṛtau yathā

kvacit
sometimes
vādayataḥ
blowing
veṇum
on the flute
kṣepaṇaiḥ
with a device of rope for throwing
kṣipataḥ
throwing stones to get fruit
kvacit
sometimes
kvacit pādaiḥ
sometimes with the legs
kiṅkiṇībhiḥ
with the sound of ankle bells
kvacit
sometimes
kṛtrima-go-vṛṣaiḥ
by becoming artificial cows and bulls
vṛṣāyamāṇau
imitating the animals
nardantau
roaring loudly
yuyudhāte
They both used to fight
parasparam
with one another
anukṛtya
imitating
rutaiḥ
by resounding
jantūn
all the animals
ceratuḥ
They used to wander
prākṛtau
two ordinary human children
yathā
like

Sometimes Kṛṣṇa and Balarāma would play on Their flutes, sometimes They would throw ropes and stones devised for getting fruits from the trees, sometimes They would throw only stones, and sometimes, Their ankle bells tinkling, They would play football with fruits like bael and āmalakī. Sometimes They would cover Themselves with blankets and imitate cows and bulls and fight with one another, roaring loudly, and sometimes They would imitate the voices of the animals. In this way They enjoyed sporting, exactly like two ordinary human children.