Here's what Venus in the third house signifies:
Venus in the third house is very favourable, giving much love of art and refined literature, poetry, music, painting and all the higher attributes of the mind and mental faculties. The mental qualifications are of the highest, making the mind bright, hopeful, peaceful and harmonious. When Venus is in good aspect to the Moon or in conjunction with Mercury this position considerably modifies an otherwise adverse horoscope, for the mind is naturally inclined to be pure and free from vice or evil intent.
When afflicted the mind is over-sensuous and inclined too much to pleasure and gay society, but not wholly unfortunate unless Mercury and the Moon are also in adverse aspect. It is a position very favourable for travel and gives many journeys taken for pleasure, or those out of which pleasure eventually comes. It denotes favourable relatives, and success or gain through their aid. Persons born under positive signs are favoured mentally by this position, and those born under negative signs gain more through the feelings and emotions ; therefore the former may have literary and poetical ability and the latter musical talent and ability to draw or paint.