| Honorific Prefix: | The Right Honourable |
| The Lord De L'Isle and Dudley | |
| Honorific Suffix: | DL |
| Birth Name: | Philip Sidney |
| Birth Date: | 1828 1, df=y |
| Birth Place: | London, England |
| Death Place: | Westminster, London |
| Residence: | Penshurst Place |
| Education: | Eton College |
| Parents: | Philip Sidney, 1st Baron De L'Isle and Dudley Lady Sophia FitzClarence |
| Spouse: | |
| Children: | 5 |
| Relatives: | William IV (grandfather) Sir John Shelley-Sidney, 1st Baronet (grandfather) |
Philip Sidney, 2nd Baron De L'Isle and Dudley DL (28 January 1828 – 17 February 1898) was an English Peer.
Sidney was born in London, England on 28 January 1828. He was the youngest child and only son born to Philip Sidney, 1st Baron De L'Isle and Dudley and the former Lady Sophia FitzClarence. His mother was an illegitimate daughter of King William IV and his mistress, the actress Dorothea Jordan. His father was the only son of Sir John Shelley-Sidney, 1st Baronet and Henrietta Hunloke and was a first cousin of poet Percy Bysshe Shelley.
Sidney was an Officer in the Royal Horse Guards, gaining the rank of Lieutenant.[2] Upon his father's death in March 1851, he succeeded as the 3rd Shelley-Sidney Baronets of Penshurst Place and the 2nd Baron De L'Isle and Dudley, of Penshurst in the County of Kent.
Lord De L'Isle and Dudley served as a trustee of the National Portrait Gallery.[3]
On 23 April 1850, Sidney was married to Mary Foulis (1826–1891),[4] the only child of Sir William Foulis, 8th Baronet of Ingleby Manor, and the former Mary Jane Ross (second daughter of Gen. Sir Charles Lockhart-Ross, 7th Baronet of Carstairs and Lady Mary Rebecca FitzGerald, eldest daughter of William FitzGerald, 2nd Duke of Leinster). Upon his marriage to Mary, he assumed the additional name of Foulis after that of Sidney by Royal Warrant on 6 June 1850, under the will of his father-in-law, but relinquished it after her death in 1891. Together, they were the parents of:[1]
Lady De L'Isle and Dudley died on 14 June 1891. He remarried on 25 January 1893 to Emily Frances Ramsay, eldest daughter of William Fermor Ramsay of Croughton Park and the former Emily Susan Tredcroft (fourth daughter of Rev. Robert Tredcroft, Prebendary of Chichester Cathedral).[5]
Lord De L'Isle and Dudley died at Westminster, London on 17 February 1898 and was buried at Penshurst. After his death, his widow married Sir Walter Stirling, 3rd Baronet in February 1903; they divorced in 1909. She died on 3 November 1926.[1]
Through his youngest son William, he was posthumously the grandfather of William Philip Sidney, who was created 1st Viscount De L'Isle, of Penshurst in the County of Kent on 12 January 1956.[6]