Simplicity 5865 vintage sewing pattern, dated 1983.

Toddlers' Dress and Romper:

Dress V. 1 & 2 pleated to yoke has back loop and button closing, collar and short set-in sleeves gathered to armholes and to sleeve bands...collar and sleeve bands are contrasting. V. 1 has braid trim. V. 2 has ribbon trim. Romper V. 3 and 4 has front zipper, buttoned tabs and optional snap fastened crotch. Braid trimmed V. 3 has short set-in sleeves, ribbon tie and contrasting collar, sleeve bands and tabs. Top-stitched V. 4 is sleeveless. All garments have optional purchased applique. 

Size 3:

Chest: 22  inches / 53 cm

Waist 20 1/2 inches / 51 cm

Pattern is UNCUT and factory folded. Envelope is in good vintage condition, with an ink mark on the front.

More children's patterns here:

http://allthepreciousthings.com/collections/baby-and-children